Assessing thickness and stiffness of superficial/deep masticatory muscles in orofacial pain: an ultrasound and shear wave elastography study

Examination of the masseter muscle in patients with hemifacial microsomia using high-frequency ultrasound and shear wave elastography

BACKGROUND

This study aimed to prospectively investigate the reference values for masseter muscle thickness and hardness using ultrasonography and shear wave elastography, respectively, in patients with hemifacial microsomia (HFM).

METHODS

We enrolled 51 patients, aged 5-20 years, with HFM including 31 males and 20 females. The upper-lower, left-right, and anterior-posterior diameters of 102 masseter muscles and stiffness of 98 masseter muscles were determined by examining the unaffected and affected sides of each participant's face.

RESULTS

The upper-lower, left-right, and anterior-posterior diameters of the masseter muscle were significantly smaller at rest (4.26 ± 0.83, 2.94 ± 0.75, and- 0.80 ± 0.25 cm, respectively) and during contraction (3.95 ± 0.78, 2.71 ± 0.78, and 0.87 ± 0.29 cm, respectively) in the affected side than those in the healthy side (5.45 ± 0.66, 3.87 ± 0.49, and 0.97 ± 0.20 cm, respectively, at rest and 4.99 ± 0.45, 3.49 ± 0.53, and 1.07 ± 0.23 cm, respectively, during contraction, p < 0.05). In the resting state, the hardness of the masseter muscle on the affected side (0.77 ± 0.66 m/s) was significantly greater than that on the healthy side (0.42 ± 0.41 m/s; p < 0.05). The magnitude of changes in the upper-lower, left-right, and anterior-posterior diameters of the biting muscle in the occlusal state were significantly smaller on the affected side (-0.30 ± 0.27, -0.23 ± 0.17, and 0.08 ± 0.08 cm, respectively) than those in the healthy side (-0.47 ± 0.38, -0.37 ± 0.25, and 0.10 ± 0.12 cm, respectively, p < 0.05).

CONCLUSIONS

The knowledge of these values allows for better understanding of the disease characteristics of HFM, which may be used for its diagnosis, treatment, and prognosis. Patients experiencing different severity levels exhibited significant differences in the morphology and function of the masseter muscle on the affected-side (p < 0.05).

EVIDENCE LEVEL

Level III.

Ultrasound Assessment of Facial and Neck Aging: A Noninvasive Approach to a Minimally Invasive Treatment

This technical note explores the diagnostic potential of ultrasound in assessing age-related changes in the soft tissues of the lower face and neck, with a primary focus on identifying causes of contour deformities and guiding minimally invasive rejuvenation procedures. Seventeen clinical patients with various age-related soft-tissue changes were subjected to ultrasound assessments, targeting issues such as soft-tissue sagging, supra- and subplatysmal adipose tissue excess, platysma thickness, and localization of ptotic platysma strands. The ultrasound examinations successfully identified specific anatomical features contributing to age-related soft-tissue changes in all 17 patients. This information guided tailored treatment plans, resulting in remarkable esthetic improvements in each case. The discussion emphasizes ultrasound's invaluable role as a diagnostic tool for precisely identifying soft-tissue alterations in the lower face and neck. The noninvasive nature and high spatial resolution of ultrasound make it particularly effective for this purpose. The corrective methods guided by ultrasound findings proved to be minimally invasive and yielded successful outcomes in all cases, promoting high levels of patient satisfaction. The study highlights the underutilization of ultrasound's diagnostic potential in clinical practice and highlights the importance of its incorporation into routine assessments. Ultrasound emerges as a cost-effective, noninvasive, and accessible means of accurately diagnosing age-related soft-tissue changes, empowering clinicians to tailor rejuvenation procedures to each patient's unique needs. The hope is that by emphasizing its utility, this study encourages the broader adoption of ultrasound in clinical practice.

Feasibility of shear wave elastography for evaluating lens stiffness in patients with age-related cataracts: A quantitative analysis

Background

Shear wave elastography (SWE) is a novel imaging technique that provides quantitative assessments of tissue stiffness. This non-invasive method offers real-time, quantitative measurements and has been widely applied to various tissues, providing valuable diagnostic insights.

Purpose

This study aimed to investigate the feasibility of using SWE to evaluate the stiffness of the lens in patients with age-related cataracts.

Materials and methods

A comparative analysis involving 92 patients diagnosed with age-related cataracts and 39 healthy controls was conducted. Lens stiffness was quantified using SWE measurements. The lens nucleus of all participants was graded based on the Lens Opacities Classification System II (LOCS II). Correlations between the stiffness of the lens and age were also analyzed.

Results

The study indicates that both the stiffness of the lens and the lens nucleus were significantly higher in patients with age-related cataracts compared to healthy controls (P < 0.001). In patients with age-related cataracts, although lens nucleus stiffness variations across different grades of cataract severity were not statistically significant, all grades displayed increased stiffness relative to healthy controls. Additionally, a significant positive correlation between lens stiffness and age was observed in all participants (P < 0.001).

Conclusion

SWE appears to be a promising imaging technique for quantitatively assessing the mechanical characteristics of the lens in patients with age-related cataracts.

Reliability of Ultrasound Shear Wave Elastography for Evaluating Psoas Major and Quadratus Lumborum Stiffness: Gender and Physical Activity Effects

OBJECTIVE

We aimed to assess the reliability of quantifying psoas major (PM) and quadratus lumborum (QL) stiffness with ultrasound shear wave elastography (SWE), and to explore the effects of gender and physical activity on muscle stiffness.

METHODS

Fifty-two healthy participants (18-32 y) were recruited. To determine reliability, 29 of them underwent repeated SWE measurements of PM and QL stiffness by an operator on the same day. The intra-class correlation coefficients (ICC3,1), standard error of measurement (SEM) and minimal detectable change with 95% confidence interval (MDC95) were calculated. The rest participants underwent a single measurement. Two-way MANCOVA was conducted for the effects of gender and physical activity on muscle stiffness.

RESULTS

The observed reliability for PM (ICC3,1 = 0.89-0.92) and QL (ICC3,1 = 0.79-0.82) were good-to-excellent and good, respectively. The SEM (kPa) was 0.79-1.03 and 1.23-1.28, and the MDC95 (kPa) was 2.20-2.85 and 3.41-3.56 for PM and QL, respectively. After BMI adjustment, both gender (PM: F = 10.15, p = 0.003; QL: F = 18.07, p < 0.001) and activity level (PM: F = 5.90, p = 0.005; QL: F = 6.33, p = 0.004) influenced muscle stiffness. The female and inactive groups exhibited higher stiffness in both muscles.

CONCLUSION

SWE is reliable for quantifying the stiffness of PM and QL. Female and physical inactivity may elevate PM and QL stiffness, underscoring the importance of accounting for these factors in muscle stiffness investigations. Larger prospective studies are needed to further elucidate their effects.